[ACCEPTED]-Cannot Checkin in TFS 2013 - Value cannot be null Parameter name: format-tfs

Accepted answer

Score: 63

I got similar issue. It got resolved by 2 closing the visual studio and opening it 1 again.

Score: 2

For anyone using VS2017:

I was able to resolve 2 by clearing the contents of the cache folder 1 first:

C:\Users\UserName\AppData\Local\Microsoft\Team Foundation\7.0\Cache

Restart and Run As Admin and it should be resolved.

Score: 1

Do you have the applicable updates for VS2012 5 to connect to VS2013?

According to Compatibility between Team Foundation clients and Team Foundation Server, under 4 TFS 2013 client support for VS2012:

Requires latest Visual Studio 3 2012 update. Supports Git with Visual Studio 2 Tools for Git extension.

The latest VS2012 1 update is Update 4.

Score: 1

I had the same error message when I tried 4 to annotate a field with RegularExpression 3 data annotation and the error message I 2 tried to get from Resources didn't exist 1 (a merge issue).

[RegularExpression(@"^-?\d{1,3}([.,]\d+)?$", 
        ErrorMessageResourceType=typeof(Resources.Template),
        ErrorMessageResourceName="latitude_incorrect")]
    public Nullable<decimal> Latitude { get; set; }

Score: 1

Possibly your visual studio needs to be 1 opened with a "Run as administrator"

Score: 0

You can get help from here and it is working 1 for my end.. https://social.msdn.microsoft.com/Forums/en-US/3fe743f8-8d03-462f-823c-f93b2f973af8/visual-studio-2017-team-explorer-value-cannot-be-null-parameter-name-source?forum=tfsversioncontrol

Source: stackoverflow.com